VMware VSA vs. StorMagic SvSAN FAQ Comparison

*NOTE* - this FAQ is Based on VMware’s VSA FAQ, none of VMware’s Questions or Answers have been changed and no additional questions have been added. This is FAQ is a direct comparison between VMware’s answers and StorMagic’s, All Copy Right is acknowledged

A: SvSAN can be configured with a virtual vCenter on the HA cluster or a Physical vSphere host separate from the cluster. SvSAN storage should not be from the same RAID/Disk where the ESX OS is installed and SvSAN VM is running.

Scalability

Q. What do I do when I want to add an actual SAN or NAS in future?

A: You can transition from VMware VSA to your new SAN or NAS without service disruption if you use Storage vMotion.

A: You can transition from SvSAN to your new SAN or NAS without service disruption using Storage vMotion.

Q: What is the limit on the number of hosts?

A: VSA v1.0 scales to support up to three virtualized hosts per instance.

A: Up to 8 Initiator sessions can connect to an iSCSI target on the SvSAN. This means that 8 ESX hosts can simultaneously access the same iSCSI target on the SvSAN or 4 Hosts could have 2 paths to an iSCSI target. The initiator limit is imposed on a target and not the SvSAN itself which means 8 hosts could access one target and an additional 8 hosts accessing another. Performance implications could arise depending on the speed of the underlying storage.

Q. Can you add JBOD or external disks to this configuration?

A: No. VSA v1.0 does not allow for external disk capacity. You can add more internal capacity (if available) for scalability.

A: You can assign additional VMDKs from other locations which could be hosted on an external JBOD or SAN.

Q. Do I need to buy external storage with VSA?

A: vSphere Storage Appliance (VSA) is a software product that transforms the server's internal storage from several server hosts into a single shared storage resource. This means dedicated shared storage hardware (such as SANs) are no longer required for several servers to access the same data, thereby further simplifying IT.

A: Same answer as VMware

Q. Can I add additional nodes or storage capacity once I have set up VSA?

A: If additional disk(s) are added to a host’s controller, the SvSAN pools and targets can be extended to encompass it/them. Additional nodes can be added to a vSphere cluster and can log into SvSAN targets using the VMware iSCSI initiator.

Availability

Q. How does VSA protect the data?

A: All VSA datastores have two levels of protection. - Network mirror between servers- Local raid within each server

A: SvSAN has two levels of protection

- Local RAID on the server - SvSAN Mirrored targets are active-active so either host can fail

Q. What happens when a disk is lost on the node?

A: The local network mirrors within the node to protect against local disk failure.

A: If the local RAID configuration is redundant the RAID will protect the data. In the event 2 disks fail or the RAID is not redundant the host or VMware will simply switch iSCSI paths to the second appliance without interruption.

Q. What happens when a node (physical server) in a cluster fails?

A: The network mirroring across nodes will protect against node failure.

A: SvSAN mirrored targets are active-active so Virtual Machines will be restarted on the second server via VMware HA.

Compatibility and requirements

Q. Is there any limitation on the kind of server that will be supported with the VSA?

*NOTE* - this FAQ is Based on VMware’s VSA FAQ, none of VMware’s Questions or Answers have been changed and no additional questions have been added. This is FAQ is a direct comparison between VMware’s answers and StorMagic’s, All Copy Right is acknowledged